X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=qdd.cpp;h=522957d3f8de83afd17a291d8fb4f4eb460af866;hb=34138d5b1a1302a7a1050fd46d2fb95c0186140a;hp=8c8196dfdcab8bc537901c27d5ff872d08581898;hpb=5533268a1f4f8017beb99ae60c4d1bdb3a7228f0;p=narabu

diff --git a/qdd.cpp b/qdd.cpp
index 8c8196d..522957d 100644
--- a/qdd.cpp
+++ b/qdd.cpp
@@ -29,7 +29,8 @@ struct RansDecodeTable {
 	int cum2sym[prob_scale];
 	RansDecSymbol dsyms[NUM_SYMS];
 };
-RansDecodeTable decode_tables[16];
+#define NUM_TABLES 8
+RansDecodeTable decode_tables[NUM_TABLES];
 
 static const unsigned char std_luminance_quant_tbl[64] = {
 #if 0
@@ -55,10 +56,34 @@ static const unsigned char std_luminance_quant_tbl[64] = {
 };
 
 
-int pick_stats_for(int y, int x)
+const int luma_mapping[64] = {
+	0, 0, 1, 1, 2, 2, 3, 3,
+	0, 0, 1, 2, 2, 2, 3, 3,
+	1, 1, 2, 2, 2, 3, 3, 3,
+	1, 1, 2, 2, 2, 3, 3, 3,
+	1, 2, 2, 2, 2, 3, 3, 3,
+	2, 2, 2, 2, 3, 3, 3, 3,
+	2, 2, 3, 3, 3, 3, 3, 3,
+	3, 3, 3, 3, 3, 3, 3, 3,
+};
+const int chroma_mapping[64] = {
+	0, 1, 1, 2, 2, 2, 3, 3,
+	1, 1, 2, 2, 2, 3, 3, 3,
+	2, 2, 2, 2, 3, 3, 3, 3,
+	2, 2, 2, 3, 3, 3, 3, 3,
+	2, 3, 3, 3, 3, 3, 3, 3,
+	3, 3, 3, 3, 3, 3, 3, 3,
+	3, 3, 3, 3, 3, 3, 3, 3,
+	3, 3, 3, 3, 3, 3, 3, 3,
+};
+
+int pick_stats_for(int x, int y, bool is_chroma)
 {
-	if (x + y >= 7) return 7;
-	return x + y;
+	if (is_chroma) {
+		return chroma_mapping[y * 8 + x] + 4;
+	} else {
+		return luma_mapping[y * 8 + x];
+	}
 }
 
 uint32_t read_varint(FILE *fp)
@@ -103,32 +128,32 @@ int main(void)
 		exit(1);
 	}
 
-	for (unsigned table = 0; table < 16; ++table) {
+	uint32_t sign_bias[NUM_TABLES];
+	for (unsigned table = 0; table < NUM_TABLES; ++table) {
 		uint32_t cum_freq = 0;
 		for (unsigned sym = 0; sym < NUM_SYMS; ++sym) {
 			uint32_t freq = read_varint(fp);
 			fprintf(stderr, "sym=%u/%u: freq=%u\n", sym, NUM_SYMS, freq);
-			RansDecSymbolInit(&decode_tables[table].dsyms[sym], cum_freq, freq);
+			RansDecSymbolInit(&decode_tables[table].dsyms[(sym + 1) & 255], cum_freq, freq);
 			for (uint32_t i = 0; i < freq; ++i) {
-				decode_tables[table].cum2sym[cum_freq++] = sym;
+				if (cum_freq < prob_scale)
+					decode_tables[table].cum2sym[cum_freq] = (sym + 1) & 255;
+				++cum_freq;
 			}
 		}
+		sign_bias[table] = cum_freq;
+		printf("sign_bias=%u (of %d)\n", sign_bias[table], prob_scale * 2);
 	}
 
 	// loop over all coefficients
 	for (unsigned y = 0; y < 8; ++y) {
 		for (unsigned x = 0; x < 8; ++x) {
-			unsigned tbl = pick_stats_for(x, y);
+			unsigned tbl = pick_stats_for(x, y, false);
 		
 			RansState rans = 0;
 
-			//unique_ptr<uint8_t[]> rans_bytes(new uint8_t[num_rans_bytes]);
-			//unique_ptr<uint8_t[]> sign_bytes(new uint8_t[num_sign_bytes]);
 			unique_ptr<uint8_t[]> rans_bytes;
-			unique_ptr<uint8_t[]> sign_bytes;
 			uint8_t *rans_ptr = nullptr;
-			uint8_t *sign_ptr = nullptr;  // optimize later
-			uint32_t sign_buf = 0, sign_bits_left = 0;
 
 			// loop over all DCT blocks
 			for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
@@ -138,22 +163,7 @@ int main(void)
 					rans_bytes.reset(new uint8_t[num_rans_bytes]);
 					fread(rans_bytes.get(), 1, num_rans_bytes, fp);
 
-					uint32_t val = read_varint(fp);
-					uint8_t free_sign_bits = val & 0x7;
-					uint32_t num_sign_bytes = val >> 3;
-					sign_bytes.reset(new uint8_t[num_sign_bytes]);
-					fread(sign_bytes.get(), 1, num_sign_bytes, fp);
-
-					sign_ptr = sign_bytes.get();
-					if (free_sign_bits == 0) {
-						sign_buf = *sign_ptr++;
-						sign_bits_left = 8;
-					} else {
-						sign_buf = *sign_ptr++ >> free_sign_bits;
-						sign_bits_left = 8 - free_sign_bits;
-					}
-
-					printf("%d,%d: read %d rANS bytes, %d sign bytes\n", x, y, num_rans_bytes, num_sign_bytes);	
+					printf("%d,%d: read %d rANS bytes\n", x, y, num_rans_bytes);
 					//printf("first bytes: %02x %02x %02x %02x %02x %02x %02x %02x\n", rans_bytes[0], rans_bytes[1], rans_bytes[2], rans_bytes[3], rans_bytes[4], rans_bytes[5], rans_bytes[6], rans_bytes[7]);
 
 
@@ -162,25 +172,24 @@ int main(void)
 					RansDecInit(&rans, &rans_ptr);
 				}
 				for (unsigned xb = 0; xb < WIDTH; xb += 8) {
-					uint32_t k = decode_tables[tbl].cum2sym[RansDecGet(&rans, prob_bits)];
-					//printf("reading symbol, rans state = %08x\n", rans);
-					RansDecAdvanceSymbol(&rans, &rans_ptr, &decode_tables[tbl].dsyms[k], prob_bits);
-					//printf("done reading symbol, rans state = %08x\n", rans);
+					uint32_t bottom_bits = RansDecGet(&rans, prob_bits + 1);
+					uint32_t sign = 0;
+					if (bottom_bits >= sign_bias[tbl]) {
+						bottom_bits -= sign_bias[tbl];
+						rans -= sign_bias[tbl];
+						sign = 1;
+					}
+					uint32_t k = decode_tables[tbl].cum2sym[std::min(bottom_bits, prob_scale - 1)];
+					RansDecAdvanceSymbol(&rans, &rans_ptr, &decode_tables[tbl].dsyms[k], prob_bits + 1);
 					assert(k <= ESCAPE_LIMIT);
 					if (k == ESCAPE_LIMIT) {
 						k = RansDecGet(&rans, prob_bits);
 						assert(k >= ESCAPE_LIMIT);
-						//printf("reading escape symbol, rans state = %08x\n", rans);
 						RansDecAdvance(&rans, &rans_ptr, k, 1, prob_bits);
 					}
-					if (k != 0) {
-						if (sign_bits_left == 0) {
-							sign_buf = *sign_ptr++;
-							sign_bits_left = 8;
-						}
-						if (sign_buf & 1) k = -k;
-						--sign_bits_left;
-						sign_buf >>= 1;
+					if (sign) {
+						assert(k != 0);
+						k = -k;
 					}
 
 					// reverse